This invention relates to an electric noise absorber for absorbing electric noise that is generated within an electronic device or that enters the device from the outside through an electric cable.
As a method for absorbing electric noise, it is well-known that surrounding an electric cable with a magnetic substance, such as ferrite, reduces electric noise on the electric cable. For example, in Japan published unexamined utility model application No. 63-39997, two pieces of half ring-shaped ferrite are accommodated in a case, through which an electric cable passes. In another conventional electric noise absorber, two pieces of half ring-shaped ferrite are fixed to an electric cable with adhesive tape. In the related-art devices, the electric noise absorbers can be attached to and detached from electric cables without removing installed cables because the ferrite is divided in two, and these absorbers can be moved to the most effective position to reduce electric noise. However, these related-art electric noise absorbers are large and their installation operations are very tedious.
Fixing ferrite to an electric cable with adhesive tape is inconvenient because installation operations are complicated and the adhesive tape must be removed from and attached to cables again whenever the position of the fixed ferrite needs to be changed.
When two pieces of ferrite are accommodated in a case, an electric cable can be easily fixed between the two pieces of ferrite. However, because the case must contain the ferrite pieces and have elastic units for securing the surfaces of the two ferrite pieces together, the case must be large and its shape complicated.